YES!!! I have found plenty before now, one was a little old lady who had all her christmas money in it. I know how I would feel if it happened to me and someone pocketed the cash.
I once lost my wallet when I was 15 it had my very hard earned paper money in it and bus pass. Someone posted it back to me 18 months later the money was gone though.
Be careful if you hand it into a shop though, I did this once my mum went back an hour later to ask if it had been claimed and the same shop assistants said 'What purse'?